Tan or yellow leaf spot

Area of impact: Leaf

Description: Small yellow-brown spots that grow into larger oval-shaped brown blotches. As the lesions merge portions of the leaf yellow and die. Small dark brown spots may be found at the center of the lesion.

Pathogen involved: Pyrenophora tritici-repentis (a fungus)

Timing/Conditions: Most likely in the spring after extended periods of leaf wetness.

Contributing factors: The fungus oversummers in infested wheat stubble. Shortened or continuous wheat rotations and reduced tillage contribute to the disease.

Management practices: Rotate out of wheat for two or more years; avoid excessively dense lush stands and bury infested wheat stubble.

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